IF statement, delimiters, blanks in spreadsheet

[resolved]

I would like to replicate the following spreadsheet command in the HP Prime spreadsheet

=if(a2="";"";ATAN(b2/a2))

if I divide by zero or a blank cell I get an error message. If I use the above command on a spreadsheet in my computer, the command clears the error messages so summation further down can still calculate.

I have tried using ',' or ';' as delimiters
I have tried suing "" or '' for blank cells, but nothing worked and there is nothing in the manual on this topic, and internet searches bore little fruit

thanks for the help